Magnetic hammer



F. G. CLARK MAGNETIC HAMMER March 9, 1954 Filed March 27, 1950 INVENTOR.

flfforrzes s.

Patented Mar. 9, 1954 MAGNETIC HAMMER,

Frederick G. Clark, Buffalo, N. Y., assignor of one-half to Wade Stevenson, Buffalo, N. Y.

Application March 27, 1950, Serial No. 152,068

9 Claims.

This invention relates to improvements in magnetic hammers on which nails or other articles to be driven are held by magnetic force on the striking faces of the hammers in position to be driven.

Hammers with magnetized steel heads are well known. However, the magnetism of hammers of this type i relatively weak, thus limiting the use to which these hammers can be put. Furthermore, repeated blows with the magnetized hammer would result in decreasing the magnetic strength of the hammer so that eventually hammers of this type would not have sufiicient magnetism to make them serviceable in connection with the driving of larger nails or the like. Certain alloys are now available which ar capable of exerting very much greater magnetic force than steel, but these alloys are relatively brittle, and consequently, hammer heads made of this alloy would not have the strength and toughness necessary for the use for which hammers are customarily employed.

One of the objects of this invention is to provide a magnetic hammer having a head made of a grade of steel which is suitable for withstanding the blows to which hammer heads are ordinarily subjected and having incorporated therein a powerful magnet arranged in the hammer head in such manner that the impacts resulting when the hammer strikes an object will not damage the magnet. A further object is to provide a hammer head of this type with cushioning means for protecting the magnet against shocks resulting from the hammer striking a nail or other object. A further object is to provide hammers which are so constructed that the force of the magnet incorporated therein is concentrated on the middle portion of the striking face of the hammer.

Other objects and advantages will be apparent from the following description of one embodiment of the invention and the novel features will be particularly pointed out hereinafter in connection with the appended claims.

In the accompanying drawings:

Fig. 1 is an elevation, partly in section, of a magnetic hammer embodying this invention.

Fig. 2 is an end view thereof.

Fig. 3 is an elevation, partly in section, of a magnetic hammer of modified construction.

Fig. 4 is an end view thereof.

Fig. 5 is an elevation, partly in section, of a magnetic hammer of still another modified form.

Fig. 6 is an end view thereof.

In accordance with my invention, I provide the head of the hammer with a body portion having an aperture or cavity in which a magnet may be contained. The magnet is so mounted that one pole thereof is in contact with or in close proximity to a steel part which forms at least a portion of the striking face of the hammer head and the steel part is so mounted on the hammer head that blows or impacts on the steel part are transmitted directly to the body portion of the hammer head, thus protecting the magnet against damage by such blows or impacts.

If desired, the hammer head may also be provided with suitable cushioning or resilient means for protecting the magnet against shocks. My improvements may be applied to hammer heads 15 of various shapes and sizes.

Referring to Figs. 1 and 2, 10 represents the body portion of a hammer head mounted on a handle II. This hammer body has a cavity or aperture extending inwardly from one end thereof and into which a bar magnet 12 may be inserted. In the particular construction shown, the cavity or aperture is in the form of a cylindrical bore and the magnet is also of cylindrical form to fit into the bore. Cavities or apertures of other suitable form may be used, if desired.

In order to protect the magnet from the shocks resulting from the blows of the hammer, an insert member or part is provided which is made of a material which can carry and transmit the magnetic flux of the magnet and which is of sufficient strength and toughness to form at least a part of the striking face of the hammer. This insert member or part may be of any suitable or desired form and may be secured or attached to the body of the hammer head in any desired manner. In the particular construction illustrated by way of example, an insert member or part I4 is provided, which extends across the open end of the aperture in which the magnet is located and which is in contact or closely adjajacent to the magnet I2. This steel insert member or part 14 is provided with an annular flange or part I5 which is formed to engage a part of the hammer head about the aperture therein in such a manner that any blows on the steel insert part [4 will be transmitted directly to the body of the hammer head, thus preventing damage to the magnet l2.

The steel member or insert I4 may be held in place on the body portion of the hammer head in any suitable or desired manner, and in the construction shown for this purpose, a cap I1 is provided which has a threaded connection with a correspondingly threaded part of the body portion of the hammer head and which engages the annular flange I5 of the steel insert I4 so as to clamp this flange against the end of the body portion ID. The end face of this cap, consequently, forms a part of the striking face of the hammer about the steel insert I5. Any other means for securing the cap or holding member on the body portion I may be provided.

Additional protection to the magnet to prevent it from receiving shocks may be provided, if desired, and in the construction shown for this purpose, a cushioning member I9 is provided at the inner end of the aperture in which the magnet I2 is arranged. This cushioning member may be of any suitable or desired form, and in the construction illustrated is formed of a disk of rubber or rubber-like material against which the inner end of the magnet I2 bears.

In order to provide the maximum magnetic force on the steel insert I4 so as to attract nails or the like and hold them in correct relation to the striking face of the hammer, means are provided in the various figures for preventing the magnetic lines of force from passing freely from one pole of the magnet to the other and thus decreasing the magnetic force available for acting on nails or the like to be held on the striking face of the hammer. This is accomplished by encasing all or a major portion of the magnet in non-magnetic material. In the construction shown for this purpose, in Fig. l, the body III of the hammer head is made of a substantially non-magnetic material, such for example as bronze or certain stainless steel alloys and the cap I! is also made of a non-magnetic material. The magnet I2 is of the bar type, having its poles at opposite ends thereof, and consequently, when a nail or other magnetic article is held on the striking face of the hammer, a large proportion of the lines of force will pass through the nail or other article from the outer pole of the magnet and through the steel insert I4 and then back through the air and a 'part of the body I0 to the inner pole of the magnet.

By means of the construction described, the nail or other object to be driven by the hammer will be attracted only by the steel insert I4, and consequently, such object will be held by magnetic force on the middle portion only of the striking face of the hammer. This assures a correct positioning of such objects so that they can easily be correctly started in the wood or other material into which they are to be driven.

In Figs. 3 and 4, the hammer head I0 is similar in form to the one shown in Figs. 1 and 2, but in this construction, the body portion In may be made of magnetic material. In order to prevent short-circuiting of the magnetic force through the body portion of the hammer head, the cap I! which holds the steel insert I4 in place is made of non-magnetic material and a portion of the sides of the magnet is encased in non-magnetic material. For this purpose, a suitablesleeve or casing 2| of non-magnetic 1naterial extends about the major portion of the length of the magnet I2 from the outer end thereof, leaving only a small portion of the inner end of the magnet in contact with the body portion III; A part of the non-magnetic material is also disposed between the steel insert member or part I4 and the end of the body portion II], and in the construction shown by way of example, the sleeve 2I is provided at its outer end with a flange 22 which extends across the end of the threaded portion of the body portion Ill, so that the flange I5 of the steel part I4 bears against the non-magnetic flange 22. In the use ofthis hammer, when a nail or the like is held on the striking face thereof, the lines of force are prevented from short-circuiting from one end of the magnet to the other end through the hammer head and, consequently, pass through the nail or other article held by the magnetic steel insert I4, and around the exterior of the sleeve I2 from one pole of the magnet to the other.

In the construction shown in Fig. 5, another type of hammer is disclosed with an aperture in the head thereof in which the magnet I2 is located. In this construction, the body portion 25 of the hammer head is made of magnetic material and a cap 26 secured on the end of the body portion is also made of magnetic material. 21 represents the steel insert or part which is arranged in contact with one pole of the magnet I2. The cap 25 may have a screw-threaded connection. with the body portion and a pin 28, may be driven into alined holes in the cap, and body portion. to ensure a secure connection between the cap and the body portion. In this case, a sheath or casing of non-magnetic material extends about the greater portion of the magnet and the steel insert member 21. For example; in the construction shown, a shell or tube 3|. of non-magnetic material is provided about the major portion of the ma net I2 and a washer or annular disk 32 of non-magnetic materialis arranged between the end of the body portion of the hammer head and the flange 33, of the steel insert 27. In order to prevent ShOI'tyCiI'Clliting of the magnetic force from one poleof the magnet to the other through the cap 26 which is also made of magnetic material, a shell of, non-magnetic material is provided which ens closes the sidesof the steel insert 21 and spaces the same from the cap 26. This non-magnetic, shell as shown includes an annular part 3.5 ex tending about the periphery of the flange 33, of the steel insert, an inwardly extending flange 36 and a shell or tubular part 312 These three; parts may bev formed integral as shown inFig, 5- so that short-circuiting of the magnetic force from the inner pole of the magnet to the steel: insert 21 is prevented.

By means of this construction, the shell 25 constitutes in effect one pole of the magnet, or a continuation thereof, since it is in direct magnetic connection through the hammer head with the pole of the magnet I2 which is located at the inner endof the aperture. The steel insert mem ber 21 constitutes the other pole of themagnet, being substantially in contact with the outer pole of the magnet I2. Consequently, a nail or other articles to be driven will be very securely held in ngagement with the striking faceof the ham-- mer, if it contacts both the steel insert member 21 and the cap 26.

By means of the constuction described, it will be obvious that hammers produced in accordance with this invention exert a very strong magneticholding power on the nails or other objects to be driven, since the magnets I2 if made of a highly magnetic alloy may exert a magnetic force many times greater than that which can be exerted, by a permanent steel magnet.

The steel insert or parts which are in direct contact with the outer pole of the magnet in all of the constructions shown are formed to bear on the end of the body portion of the hammerhead so that any blows on these steel inserts will be transmitted. directly to the body portion, thus protecting the magnet against damage."

Furthermore, the cushioning members IS-at the inner endsof the bores or recesses of the hammer:heads serve the purpose of protecting the magnets against shocks. By arranging the steel inserts in the middle portions of the striking surfaces of thehammers, the nails or other objects will be attracted toward these middle portions, thus ensuring a correctpositioning objects on the-hammer heads. 1 I

The term non-magnetic is herein used in the practical sense to designate materials of very low magnetic permeability.

It will be understood that various changes in the details, materials, and arrangements of parts which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention, as expressed in the appended claims.

I claim:

1. A magnetic hammer head having a body portion provided with an aperture extending inwardly from one end thereof, a permanent magnet arranged in said aperture, a steel member which is secured to said body portion and which forms a part of the striking face of said hammer and which is magnetized by said magnet to hold nails and the like on said hammer, and cushioning means in said hammer head and engagaing said magnet to protect the same against shocks to which said hammer head is subjeted, said steel member being mounted to transmit impacts received thereby directly to said hammer head, to protect said magnet against said impacts.

2. A magnetic hammer head having a body portion provided with an aperture extending inwardly from one end thereof, a permanent magnet arranged in said aperture with the poles thereof adjacent to the opposite ends of said aperture, a cushioning member at the inner end of said aperture against which one end of said magnet bears, and on which a magetizable steel member is held and bears against said end of said hammer head and which is arranged at the other end of said magnet and is magnetized thereby to attract nails and the like to said hammer in position to be driven, whereby impacts against said steel member are transmitted to said hammer head and are prevented from being absorbed by said magnet.

3. A hammer head according to claim 2, in which at least a portion of the sides of said magnet are encased in non-magnetic material to concentrate the magnetic force of said magnet on said steel member.

4. A magnetic hammer head having a body portion formed of non-magnetic material and provided with an aperture extending inwardly into said body portion from one end thereof, a permanent bar magnet arranged in said aperture, a steel member bridging said aperture and in operative relation to the outer end of said magnet to be magnetized thereby and forming a part of the striking face of said hammer head, and. a cap of non-magnetic material secured to said body portion and clamping said steel member thereto.

5. A magnetic hammer head having a body portion formed of non-magnetic material and provided with an aperture extending inwardly into said body portion from one end thereof, a permanent bar magnet arranged in said aperture, a steel member bridging said aperture and in operative relation to the outer end of said magnet to be magnetized thereby and forming a part of of these.

thestriking face of said hammer head, a cap of non-magnetic material secured to said body por-, tion and clamping said steel member thereto, said cap confining said steel member to the an aperture extending inwardly into said body portion from one end thereof, a permanent bar magnet arranged in said aperture, a sheath of non-magnetic material arranged about the sides of said bar magnet from the outer end thereof to adjacent to the inner end of said magnet, a steel member bridging said aperture and in operative relation to the outer end of said magnet to be magnetized thereby and forming a part of the striking face of said hammer head, a part of non-magnetic material interposed between said steel member and said body portion of said hammer, and a cap of non-magnetic material secured to said body portion and clamping said steel member thereto.

7. A magnetic hammer having a body portion formed of magnetic material and provided with an aperture extending inwardly into said body portion from one end thereof, a permanent magnet arranged in said aperture, a steel member bridging said aperture and in operative relation to the outer end of said magnet to be magnetized thereby and forming a part of the striking face of said hammer head, a sheath of nonmagnetic material extending about the sides of said magnet from the outer end thereof and terminating in spaced relation to the inner end thereof, a cap of magnetic material secured to the end of said hammer head and holding said steel member in its operative position, and an enclosure of non-magnetic material for the sides of said steel member for spacing the same from said body portion and said cap.

8. A magnetic hammer having a body portion formed of magnetic material and provided with an aperture extending inwardly into said body portion from one end thereof, a permanent magnet arranged in said aperture, a steel member bridging said aperture and in operative relation to the outer end of said magnet to be magnetized thereby and forming a part of the striking face of said hammer head, a sheath of non-magnetic material extending about the sides of said magnet from the outer end thereof and termihating in spaced relation to the inner end thereof, a cap of magnetic material secured to the end of said hammer head and holding said steel member in its operative position, an enclosure for non-magnetic material for the sides of said steel member for spacing the same from said body portion and said cap, and a resilient member arranged at the inner end of said aperture against which said magnet bears.

9. A magnetic hammer head having a body portion provided with an aperture extending inwardly from the striking end thereof, a permanent magnet arranged in said aperture, a steel member bridging said aperture and confining said magnet in said aperture, said steel member being arranged in operative relation to one end of said magnet to be magnetized thereby, the outer surface of said steel member forming a part of the striking face of said hammer head and secured thereto to prevent the magnet from being struck by parts struck by said hammer head, and means 7 of row magnetic condutivity' separating the outer endof said magnet and said s'teel membmf from said body portion of said hammer headto) concentrate the magnetic force of said magnet in=said steel member.

'- FREDERICK G. CLARK.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Boeklen Aug. 28, 1860 mimber Number Name m Cheney h ei- July 14; ms Reardon he. Get; 21 ,19 Ullman et all Dec. 4, 1m; Hertz" he Sept. 27, FOREIGN PATENTS Country Date Great Britain Nov. 19 ,-189fl: 

